drm/dp/mst: always send reply for UP request

We should always send reply for UP request in order
to make downstream device clean-up resources appropriately.

Issue was that reply for UP request was sent only once.

Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Mykola Lysenko <Mykola.Lysenko@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

1 files changed, 11 insertions, 19 deletions

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 7710de6e8a55..ca92a3217465 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -1494,26 +1494,18 @@ static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
 }
 
 /* called holding qlock */
-static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
+static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
+                                       struct drm_dp_sideband_msg_tx *txmsg)
 {
-        struct drm_dp_sideband_msg_tx *txmsg;
         int ret;
 
         /* construct a chunk from the first msg in the tx_msg queue */
-        if (list_empty(&mgr->tx_msg_upq)) {
-                mgr->tx_up_in_progress = false;
-                return;
-        }
-
-        txmsg = list_first_entry(&mgr->tx_msg_upq, struct drm_dp_sideband_msg_tx, next);
         ret = process_single_tx_qlock(mgr, txmsg, true);
-        if (ret == 1) {
-                /* up txmsgs aren't put in slots - so free after we send it */
-                list_del(&txmsg->next);
-                kfree(txmsg);
-        } else if (ret)
+
+        if (ret != 1)
                 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
-        mgr->tx_up_in_progress = true;
+
+        txmsg->dst->tx_slots[txmsg->seqno] = NULL;
 }
 
 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
@@ -1907,11 +1899,12 @@ static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
         drm_dp_encode_up_ack_reply(txmsg, req_type);
 
         mutex_lock(&mgr->qlock);
-        list_add_tail(&txmsg->next, &mgr->tx_msg_upq);
-        if (!mgr->tx_up_in_progress) {
-                process_single_up_tx_qlock(mgr);
-        }
+
+        process_single_up_tx_qlock(mgr, txmsg);
+
         mutex_unlock(&mgr->qlock);
+
+        kfree(txmsg);
         return 0;
 }
 
@@ -2843,7 +2836,6 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr,
         mutex_init(&mgr->qlock);
         mutex_init(&mgr->payload_lock);
         mutex_init(&mgr->destroy_connector_lock);
-        INIT_LIST_HEAD(&mgr->tx_msg_upq);
         INIT_LIST_HEAD(&mgr->tx_msg_downq);
         INIT_LIST_HEAD(&mgr->destroy_connector_list);
         INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work);